1. Field of the Invention
The invention relates to meat-cutting devices and particularly to a power-driven meat-cutting tool adapted to be manually held and manipulated for the quick and easy removal of meat from carcasses and bones. More particularly, the invention relates to an improved handpiece construction on which the blade holder and rotatably mounted blade are attached, which is lighter in weight and more maintenance free than heretofore known handpieces.
2. Description of the Prior Art
Various styles of power-driven meat-cutting tools have been devised wherein a ring blade is rotatably mounted on a holder which in turn is mounted on a manually operated, power-driven handle or handpiece. These tools have been used for some time to facilitate the removal of meat from a carcass, primarily in a trimming operation or for removing the meat remains from the bones. These meat-cutting tools are either electrically driven or pneumatically driven. Examples of the electric meat-cutting tools are shown in U.S. Pat. Nos. 3,024,532, 3,269,010, 3,461,557, and 3,605,841.
These electrically driven tools generally consist of a tubular handpiece formed as a single, all-metallic member having a hollow bore. The annular blade holder is attached to the front portion of the handpiece with the ring blade being removably mounted thereon by various mounting arrangements. The blade is formed with gear teeth extending about the top thereof, which teeth are in driving engagement with a pinion gear mounted within the end of the handpiece. A flexible cable, one end of which is connected to a motor located adjacent to the work area, enters the rear of the handle and extends therethrough and terminates in a squared end. The squared end is engaged in a complementary opening in the rear of the pinion gear for rotatably driving the gear. The cable is surrounded by a flexible casing which terminates within an end of a hollow tubular-shaped ferrule which is located within the handpiece, with the cable continuing through the ferrule into the pinion gear. A handpiece setscrew extends radially through a threaded opening in the handpiece and terminates in a rounded end which seats in an annular groove formed in the ferrule to secure the ferrule within the handpiece. The setscrew prevents axial removal of the ferrule from the handpiece while permitting the ferrule to rotate or twist within the handle during meat-trimming procedures.
Problems have occurred with this type of construction due to the continuous turning and twisting movement of the handpiece during cutting procedures, resulting in the ferrule becoming loose within the bore of the handpiece. Continual twisting and turning movement of the handpiece will eventually enlarge the relatively small bore area within the handpiece which surrounds and supports the ferrule. Such an enlarged bore results in excessive vibration due to the high-speed rotating cable contacting the interior of the ferrule. Also, the ferrule and cable casing will pull out of the handle since the setscrew is unable to retain the same therein due to the increased bore diameter. This requires the entire handpiece to be replaced.
Another problem with known prior art electric cable-driven handpieces is that the grease which is applied to the pinion gear will work its way rearwardly within the handpiece along the casing and cable, and evenutally will drop off of the cable outside of the handpiece and onto the meat being trimmed. The grease has become sufficiently contaminated and discolored after passing through the handpiece to result in an unsanitary condition.
Still another problem with known prior handpieces is the entire metal construction thereof. These cutting knives are generally used in a cold environment that is required to maintain the meat at a low temperature. Due to the all-metal construction, the handpiece retains the cold which after a prolonged period of use becomes bothersome and uncomfortable to the operator's hand.
Another disadvantage is that damage to one part of the handpiece requires complete discarding of the handpiece due to its one-piece construction. Also, such one-piece, all-metallic construction is expensive due to the amount of metal required and the considerable amount of machining and metal working procedures to produce the final product. Furthermore, these known handpieces are difficult to clean and maintain in a sanitary condition, since they cannot be disassembled to gain access to the interior for cleaning.
No handpiece for use with an electrically driven meatcutting blade of which I am aware has eliminated many of these problems by providing a two-piece construction having means mounted within the interior of the handpiece which provides an increased bearing surface for the ferrule, which eliminates the excessive vibration problems, and in which a sealing O-ring is provided which appreciably reduces the amount of grease heretofore escaping from the handpiece while preventing outside moisture from entering the handpiece interior.